Evaluation of in vitro macrophage differentiation during space flight
Ontology highlight
ABSTRACT: We differentiated mouse bone marrow cells in the presence of recombinant macrophage colony stimulating (rM-CSF) factor for 14 days during the flight of space shuttle Space Transportation System (STS)-126. We tested the hypothesis that the receptor expression for M-CSF, c-Fms was reduced. We used flow cytometry to assess molecules on cells that were preserved during flight to define the differentiation state of the developing bone marrow macrophages; including CD11b, CD31, CD44, Ly6C, Ly6G, F4/80, Mac2, c-Fos as well as c-Fms. In addition, RNA was preserved during the flight and was used to perform a gene microarray. We found that there were significant differences in the number of macrophages that developed in space compared to controls maintained on Earth. We found that there were significant changes in the distribution of cells that expressed CD11b, CD31, F4/80, Mac2, Ly6C and c-Fos. However, there were no changes in c-Fms expression and no consistent pattern of advanced or retarded differentiation during space flight. We also found a pattern of transcript levels that would be consistent with a relatively normal differentiation outcome but increased proliferation by the bone marrow macrophages that were assayed after 14 days of space flight. There also was a surprising pattern of space flight influence on genes of the coagulation pathway. These data confirm that a space flight can have an impact on the in vitro development of macrophages from mouse bone marrow cells. MESH:Space Flight/Space Flight
Project description:Splenic red pulp macrophages (RPM) degrade senescent erythrocytes and recycle heme-associated iron. The transcription factor Spic is selectively expressed by RPM and is required for their development, but the physiologic stimulus inducing Spic is unknown. Here, we report that Spic also regulated the development of F4/80+VCAM+ bone marrow macrophages (BMM) and that Spic expression in BMM and RPM development was induced by heme, a metabolite of erythrocyte degradation. Pathologic hemolysis induced loss of RPM and BMM due to excess heme but induced Spic in monocytes to generate new RPM and BMM. Spic expression in monocytes was constitutively inhibited by the transcriptional repressor Bach1. Heme induced proteasome-dependent BACH1 degradation and rapid Spic derepression. Further, cysteine-proline dipeptide motifs in BACH1 that mediate heme-dependent degradation were necessary for Spic induction by heme. These findings are the first example of metabolite-driven differentiation of a tissue-resident macrophage subset and provide new insight into iron homeostasis. Global gene expression pattern of Spic+ monocytes, Spic- monocytes, and Spic high red pulp macrophages were compared by sorting these cells from Spic(igfp/+) splenocytes and performing microarray-based gene expression profiling. Splenocytes were prepared from Spic(igfp/+) mice and were first negatively selected for CD4, CD8, and B220 by MACS (Miltenyi Biotech) purification using the respective microbeads. Negatively selected splenocytes were then stained with anti-CD11b and anti-Ly6c and sorted for Spic+ monocytes (CD11b+Ly6c+Spic+) and Spic- monocytes (CD11b+Ly6c+Spic-). Purified RPM were obtained by staining splenocytes with anti-F4/80 and sorting for F4/80 hi Spic-EGFP hi cells.
Project description:Microgravity leads to a 10-15% loss of bone mass in astronauts during space flight. Osteoclast is the multinucleated bone resorbing cell. In this study, we used NASA developed ground based Rotary Wall Vessel Bioreactor (RWV), Rotary Cell Culture System (RCCS) to simulate microgravity (μXg) conditions and demonstrated a significant increase (2-fold) in osteoclastogenesis compared to ground based control (Xg) mouse bone marrow cultures. We further determined the gene expression profiling of RAW 264.7 osteoclast progenitor cells in microgravity by agilent microarray analysis. Gene expression pattern was functional group clustered by transcriptome analysis using gene ontology tree machine (GOTM) for cell proliferation/survival, differentiation and function. We confirm the microgravity modulated gene expression critical for osteoclast differentiation by real-time RT-PCR and Western blot analysis in murine bone marrow cultures. We identify transcription factors such as c-Jun, c-Fos, PU-1 critical for osteoclast differentiation is up-regulated in microgravity conditions. In addition, microgravity resulted in 2.3 and 2.0-fold increase in the level of cathepsin K and MMP-9 matrix metalloproteinase expression in preosteoclast cells involved in the bone resorption process respectively. We also demonstrate a significant increase in the expression levels of M-CSF receptor, c-Fms and PLCγ2 and S100A8 molecules that play an important role in Ca2+ signaling essential for osteoclast function. Further, microgravity stimulated preosteoclast cells showed elevated cytosolic Ca2+ levels compared to ground based control cells. Thus, microgravity regulated gene expression profiling in preosteoclast cells provide new insights in to molecular mechanisms and therapeutic targets of osteoclast differentiation/activation responsible for bone loss and fracture risk in astronauts during space flight mission. Microgravity associated with space flight is a challenge for normal bone homeostasis. Astronauts experience 10-15% bone loss during a space flight mission. We aimed to determine the effect of simulated microgravity on osteoclast preosteoclasts cells. RAW264.7 cells (1.5 x 106 /ml) were loaded in RCCS with DMEM containing 10% FBS for 24 h. The cells were stimulated with RANKL (80ng/ml) for 24 h to obtain preosteoclasts in parallel with ground based control cells. Total RNA was isolated using RNAzol reagent (Biotecx Labs, Houston, TX) from control (Xg) and microgravity (μXg) subjected cells and hybridized with Agilent whole mouse genome 4x44K array system. Slides were washed and scanned on an Agilent G2565 microarray scanner. Data obtained were analyzed with Agilent feature extraction and GeneSpring GX v7.3.1 software packages (Genus biosystem, Inc. Northbrook, IL, USA).
Project description:Genes expression in Ly6C+/F4/80+ inflammatory macrophages, CX3CR1+/F4/80+ tissue resident macrophages and Ly6G+/F4/80- neutrophils which were isolated from day 3 wounds in C57/B6 mice aged 8 weeks by cell sorting Ly6C+ macrophages expressed higher (over 5 folds) levels of 241 genes compared to CX3CR1+ macrophages, and 3382 genes compared to neutrophils
Project description:Microgravity leads to a 10-15% loss of bone mass in astronauts during space flight. Osteoclast is the multinucleated bone resorbing cell. In this study, we used NASA developed ground based Rotary Wall Vessel Bioreactor (RWV), Rotary Cell Culture System (RCCS) to simulate microgravity (μXg) conditions and demonstrated a significant increase (2-fold) in osteoclastogenesis compared to ground based control (Xg) mouse bone marrow cultures. We further determined the gene expression profiling of RAW 264.7 osteoclast progenitor cells in microgravity by agilent microarray analysis. Gene expression pattern was functional group clustered by transcriptome analysis using gene ontology tree machine (GOTM) for cell proliferation/survival, differentiation and function. We confirm the microgravity modulated gene expression critical for osteoclast differentiation by real-time RT-PCR and Western blot analysis in murine bone marrow cultures. We identify transcription factors such as c-Jun, c-Fos, PU-1 critical for osteoclast differentiation is up-regulated in microgravity conditions. In addition, microgravity resulted in 2.3 and 2.0-fold increase in the level of cathepsin K and MMP-9 matrix metalloproteinase expression in preosteoclast cells involved in the bone resorption process respectively. We also demonstrate a significant increase in the expression levels of M-CSF receptor, c-Fms and PLCγ2 and S100A8 molecules that play an important role in Ca2+ signaling essential for osteoclast function. Further, microgravity stimulated preosteoclast cells showed elevated cytosolic Ca2+ levels compared to ground based control cells. Thus, microgravity regulated gene expression profiling in preosteoclast cells provide new insights in to molecular mechanisms and therapeutic targets of osteoclast differentiation/activation responsible for bone loss and fracture risk in astronauts during space flight mission.
Project description:Genes expression in Ly6C+/F4/80+ inflammatory macrophages, CX3CR1+/F4/80+ tissue resident macrophages and Ly6G+/F4/80- neutrophils which were isolated from day 3 wounds in C57/B6 mice aged 8 weeks by cell sorting
Project description:Muscle injury was elicited by cardiotoxin injection into the tibialis anterior muscle. Macrophages were isolated 2 days post-injury from the regenerating muscle. We used microarray to obtain global gene expression data of muscle-derived tissue macrophage subsets. Tissue macrophages were collected from regenerating muscle samples of three animals, Ly6C+ F4/80low and Ly6C- F4/80high macrophage subsets were sorted. The global gene expression patterns of distinct macrophage subsets were analyzed on Affymetrix microarrays.
Project description:Muscle injury was elicited by cardiotoxin injection into the tibialis anterior muscle. Macrophages were isolated 2 days post-injury from the regenerating muscle. We used microarray to obtain global gene expression data of muscle-derived tissue macrophage subsets. Tissue macrophages were collected from regenerating muscle samples of three animals, Ly6C+ F4/80low and Ly6C- F4/80high macrophage subsets were sorted. The global gene expression patterns of distinct macrophage subsets were analyzed on Affymetrix microarrays.
Project description:Macrophages (MΦs), osteoclasts (OCs) and dendritic cells (DCs) are closely related, but the exact steps in their lineage commitment are unclear. We here dissect B220-CD11blow/negc-Kit+c-Fms+ mouse bone marrow (BM) cells into a CD27+Flt3+ progenitor popula
Project description:Macrophages have distinct characteristics depending on their microenvironment. We performed proteomic analysis between M1 and M2 macrophages and found that cellular metabolism is the key regulator of macrophage function. We used microarray to support proteomic data between M1 and M2 macrophages. M1 macrophages are obtained using cell sorting of CD45+MHCII+CD8a-F4/80+ population from C57BL/6J bone marrow cell derived heterogenous cells under GM-CSF conditioning for 7 days. M2 macrophages are differentiated with 20% L929 cell supernatant for 7 days and sorted from CD45+F4/80+CD11b+ population.
Project description:RNA-seq analysis of cardiac, renal, and liver macrophages. CD11b+F4/80+Ly6C-Ly6G- tissue resident macrophages were isolated from the heart, kidney, and liver of mice. Isolated RNA was subjected to RNA-seq to identify differentially expressed transcripts.